readline: implements keypress buffering

There was an underlying assumption in readline.emitKeypressEvents (and
by extension emitKey) that the given stream (usually process.stdin)
would emit 'data' once per keypress, which is not always the case.

This commit buffers the input stream and ensures a 'keypress' event is
triggered for every keypress (including escape codes).

Signed-off-by: Fedor Indutny <fedor@indutny.com>

lib/readline.js

@@ -893,7 +893,7 @@ function emitKeypressEvents(stream) {
   function onData(b) {
     if (EventEmitter.listenerCount(stream, 'keypress') > 0) {
       var r = stream._keypressDecoder.write(b);
-      if (r) emitKey(stream, r);
+      if (r) emitKeys(stream, r);
     } else {
       // Nobody's watching anyway
       stream.removeListener('data', onData);
@@ -947,11 +947,17 @@ exports.emitKeypressEvents = emitKeypressEvents;
 // Regexes used for ansi escape code splitting
 var metaKeyCodeReAnywhere = /(?:\x1b)([a-zA-Z0-9])/;
 var metaKeyCodeRe = new RegExp('^' + metaKeyCodeReAnywhere.source + '$');
-var functionKeyCodeReAnywhere =
-    /(?:\x1b+)(O|N|\[|\[\[)(?:(\d+)(?:;(\d+))?([~^$])|(?:1;)?(\d+)?([a-zA-Z]))/;
+var functionKeyCodeReAnywhere = new RegExp('(?:\x1b+)(O|N|\\[|\\[\\[)(?:' + [
+  '(\\d+)(?:;(\\d+))?([~^$])',
+  '(?:M([@ #!a`])(.)(.))', // mouse
+  '(?:1;)?(\\d+)?([a-zA-Z])'
+].join('|') + ')');
 var functionKeyCodeRe = new RegExp('^' + functionKeyCodeReAnywhere.source);
+var escapeCodeReAnywhere = new RegExp([
+  functionKeyCodeReAnywhere.source, metaKeyCodeReAnywhere.source, /\x1b./.source
+].join('|'));
 
-function emitKey(stream, s) {
+function emitKeys(stream, s) {
   var ch,
       key = {
         name: undefined,
@@ -970,6 +976,16 @@ function emitKey(stream, s) {
     }
   }
 
+  var buffer = [];
+  var match;
+  while (match = escapeCodeReAnywhere.exec(s)) {
+    buffer = buffer.concat(s.slice(0, match.index).split(''));
+    buffer.push(match[0]);
+    s = s.slice(match.index + match[0].length);
+  }
+  buffer = buffer.concat(s.split(''));
+
+  buffer.forEach(function(s) {
     key.sequence = s;
 
     if (s === '\r') {
@@ -1025,8 +1041,8 @@ function emitKey(stream, s) {
       // reassemble the key code leaving out leading \x1b's,
       // the modifier key bitflag and any meaningless "1;" sequence
       var code = (parts[1] || '') + (parts[2] || '') +
-               (parts[4] || '') + (parts[6] || ''),
-        modifier = (parts[3] || parts[5] || 1) - 1;
+                 (parts[4] || '') + (parts[9] || ''),
+          modifier = (parts[3] || parts[8] || 1) - 1;
 
       // Parse the key modifier
       key.ctrl = !!(modifier & 4);
@@ -1131,13 +1147,6 @@ function emitKey(stream, s) {
         default: key.name = 'undefined'; break;
 
       }
-  } else if (s.length > 1 && s[0] !== '\x1b') {
-    // Got a longer-than-one string of characters.
-    // Probably a paste, since it wasn't a control sequence.
-    Array.prototype.forEach.call(s, function(c) {
-      emitKey(stream, c);
-    });
-    return;
     }
 
     // Don't emit a key if no name was found
@@ -1152,6 +1161,7 @@ function emitKey(stream, s) {
     if (key || ch) {
       stream.emit('keypress', ch, key);
     }
+  });
 }
 
 

test/simple/test-readline-interface.js

@@ -214,6 +214,30 @@ function isWarned(emitter) {
   assert.equal(callCount, 1);
   rli.close();
 
+  // keypress
+  [
+    ['a'],
+    ['\x1b'],
+    ['\x1b[31m'],
+    ['\x1b[31m', '\x1b[39m'],
+    ['\x1b[31m', 'a', '\x1b[39m', 'a']
+  ].forEach(function (keypresses) {
+    fi = new FakeInput();
+    callCount = 0;
+    var remainingKeypresses = keypresses.slice();
+    function keypressListener (ch, key) {
+      callCount++;
+      assert.equal(key.sequence, remainingKeypresses.shift());
+    };
+    readline.emitKeypressEvents(fi);
+    fi.on('keypress', keypressListener);
+    fi.emit('data', keypresses.join(''));
+    assert.equal(callCount, keypresses.length);
+    assert.equal(remainingKeypresses.length, 0);
+    fi.removeListener('keypress', keypressListener);
+    fi.emit('data', ''); // removes listener
+  });
+
   if (terminal) {
     // question
     fi = new FakeInput();